This invention relates to fusing articles in a controlled atmosphere using a reflector adjacent the article to concentrate the heat energy onto the article to fuse it, and relates particularly although not exclusively to manufacturing magnetic reed contact units.
Magnetic reed contact units basically comprise a pair of reeds having blade portions which extend into opposite ends of a glass encapsulation envelope and overlap within the envelope, the ends of the envelope being sealed to the shanks of the reeds. The assembly of such contact units comprises a sequence of operations which can be performed automatically, for example, on a rotatable turret having a plurality of assembly heads.
During the assembly of these reed contact units we have experienced difficulties with the reflectors in that they become contaminated with a deposit which appears to emanate from the fused glass during sealing the ends of the glass envelope. Furthermore, the reflectors, which are made of copper plated with gold on a nickel base, suffer from diffusion of the gold owing to the high temperatures reached. In the past it has been a relatively simple matter to replace these reflectors at frequent intervals, but with or present high speed turret machine the replacement of these reflectors has become a major drawback.